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Edible mushrooms consumed in Benin include a diversity of species including oyster mushrooms (Pleurotus ostreatus). This Oyster mushroom production is increasing in the South of the country. The study aims to evaluate their techno-functional, nutritional and sensory properties in order to optimize their exploitation in food technology and gastronomy. Therefore, 900g of Pleurotus ostreatus were produced on Oil Palm By- Products and divided into three lots of 300g for the study. Lot 1 was used to evaluate the techno-functional and nutritional parameters of fresh mushrooms. Lot 2 was brined while lot 3 was dried. Samples from all three lots were collected and used to study the variability in sensory quality by treatment. The study shows that Pleurotus ostreatus mushrooms produced in Benin have several technological-functional and nutritional benefits that can be used for food security. The luminance values (L*), red index (a*) and yellow index (b*) for fresh oyster mushrooms were respectively 74.6, 2.78 and 26.35. The hue value and the chroma value of the raw mushrooms were respectively of 5.98 and 26.49. The pH of fresh oyster mushrooms was 6.35. The water holding capacity was 11.85% and the technological yield was 88.15%. Nutritionally, the dry matter, fat, ash and protein content of the Pleurotus ostreatus were 9.8%, 2.6%, 6.7%, and 14.78% respectively. About sensorial quality, fresh and brined mushrooms were better appreciated than dried mushrooms. Overall, Pleurotus ostreatus mushrooms produced in palm residues have several techno-functional and nutritional assets and may be promoted for food and nutritional security.

Street trees are always considered a vital part of urban green infrastructure in urbanized areas through mitigating the negative effects caused by urbanization taking part in human well-being. However, little is still known about their diversity, structure and protection, mostly in Lubumbashi city in the Democratic Republic of the Congo (DR Congo), where the pace of urbanization is not only rapid but also unplanned. In this study, using an inventory, we have characterized the diversity, structure and protection measures of street trees along a land-use planning gradient in Lubumbashi for both planned and unplanned neighborhoods. From the results, a total of 1596 trees were encountered, comprising 40 species, 33 genera and 17 families, mostly dominated by exotic species (65%). In addition, most of the studied trees (63%) belonged to four species only (Jacaranda mimosifolia, Leucaena leucocephala, Mangifera indica, and Acacia auriculiformis) with Leucaena leucocephala and Jacaranda mimosifolia being highly represented in unplanned and planned neighborhoods, respectively. The most abundant diameter classes in the planned neighborhoods were those with at most 10 cm against the classes larger than 50 cm in the planned neighborhoods. In both neighborhoods, trees with protection equipment represent less than 35%. Furthermore, in planned neighborhoods notably, nearly half of the observed equipment is in a good condition. Despite the benefits associated with street trees, there is a need to reduce the proportion of exotic tree species by planting native utilitarian tree species.

Urbanisation generally causes a number of ecological problems, mostly associated with loss or degradation of green spaces. In the city of Lubumbashi (Democratic Republic of Congo), not only the health of the local vegetation has been profoundly affected due to an accelerated and uncontrolled spatial dynamics, but decision-makers and planners are also short of data likely to maximise the environmental benefits provided by woody green spaces. Hence, this study was designed to characterize the plant diversity and structure of woody green spaces in Lubumbashi. The study area was divided into urban and peri-urban zones, with respect to the urbanisation level, and data were collected utilising a circular plots-based inventory. Sixty species of trees and shrubs, belonging to 22 families, were recorded. The considered woody green spaces are dominated by miombo woodland species, but Acacia auriculiformis remained the most common species. This study suggest the existence of tree and shrub species that are typical of the urban zone and the peri-urban zone. Comparatively however, the average diameter and the basal area of trees were significantly higher in the urban woody green spaces, which seems to suggest more old trees in urban zone. Both urban and peri-urban zones had a reverse-J-shaped size class profile, with a slight jump in the largest size class. The peri-urban woody green space had more small stems, but not markedly so, and recruitment was observed in both zones. Current results are important as they may in formulating guidelines and technical tools in assessing and monitoring the degradation of woody green spaces in the city of Lubumbashi.

Three metallophyte species, Persicaria capitata, P. puncata (Polygonaceae), Conyza cordata (Asteraceae) from mineral wastes in the Zambian copper–cobalt belt were studied. This study focused on the elemental distribution in the roots, stems and leaves, using a range of techniques: micro-PIXE, SEM-EDS synchrotron XFM and XAS. The species differed in their responses to growing on Co–Cu-enriched soils: Persicaria puncata is a Co hyperaccumulator (up to 1060 μg g−1 in leaves), while Persicaria capitata and Conyza cordata are Co-excluders. All three species are Cu-accumulators. The highest concentrations of Cu–Co are in the epidermal cells, whereas in Persicaria puncata Co was also enriched in the phloem. The Co coordination chemistry shows that an aqueous Co(ii)–tartrate complex was the predominant component identified in all plants and tissues, along with a minor component of a Co(iii) compound with oxygen donor ligands. For Cu, there was considerable variation in the Cu speciation in the various tissues and across the three species. In contrast to hyperaccumulator plants, excluder and accumulator type plants have received far less attention. This study highlights the different biopathways of transition elements (Cu, Co) in hyper-tolerant plant species showing different responses to metalliferous environments.

Outcrops in the southeastern Democratic Republic of the Congo (DRC) are recognized as some of the largest copper–cobalt orebodies in the world. They support a unique vegetation with nearly 600 metallophytes that include rare and endemic species. Mineral exploitation has increased considerably in the region since the 1900s, affecting both environmental and public health. Phytostabilisation of polluted areas represents an opportunity to decrease the bioavailability of heavy metals in the highly polluted soils that result from ore extraction. Such a technique has been successfully implemented near Lubumbashi with the grass Microchloa altera. However, long-term maintenance requires a good understanding of interspecific relationships, such as competition and facilitation. This study tested the establishment success of four herbaceous species from the Katangan Copperbelt by assessing the potential role of Microchloa altera as a nurse species. Two annual and two perennial species were sown in an experiment designed to study the influence of soil amendment and vegetation cover on seedling emergence, growth, and survival. These variables were monitored during the vegetation growing season as well as resprouting success for perennials. Microchloa altera showed a distinct effect on the emergence and survival of annual and perennial species and negatively affected the growth of individuals belonging to both groups of species.

Anthropization of forest landscapes is a major threat to ecosystems and biodiversity. To gather comprehensive information on anthropization dynamics in forest landscapes, fine-scale surveys of deforestation are required, coupled with detailed analysis of both spatial transformation processes and forest patch geometry. We conducted such a comprehensive study in a monospecific Uapaca bojeri (Baill.) forest of Madagascar, between 1999 and 2013. A diachronic set of four maps was produced and deforestation rates were calculated. Spatial transformation processes were described using Bogaert et al. (2004) typology. Forest patch geometry was monitored using largest patch index, mean patch size, and squared mean patch size to describe patch size dynamics, mean shape index and area weighted mean shape index to describe patch compactness, and fractal dimension analysis to describe patch outline complexity. For fractal dimension analysis, an innovative segmented regression model (Muggeo 2008) was used to separately quantify fractal dimensions for multiple ranges of patch sizes. Our results showed a growing anthropization of the U. bojeri forest landscape in the area, through a strong yet decelerating deforestation (from − 59.5% year−1 between 1999 and 2005 to − 2.84% year−1 between 2009 and 2013), clear forest fragmentation, and a subtle yet growing-in-scale simplification of patch geometry for small forest patches. Deforestation was artisanal in nature and, in 2013, large patches were withdrawing to less accessible topographic features. Our results forecast a medium-term loss of resilience of the U. bojeri forest in the area, if no direct forest conservation measures are taken.

Recently, the growing need to complement rural and foreign sources of food and woodfuel is driving interest in urban forestry management in medium cities. The present study was designed to characterize the diversity of fruit trees in households of two rapidly developing cities in southeastern DR Congo (Lubumbashi and Kolwezi), and shed light on the sociological aspects of their management. Analyses of data collected through surveys carried out in planned and unplanned neighborhoods revealed noticeable botanical differences between the two neighborhoods within cities. In Lubumbashi, a greater number of fruit trees (6.5) and species (5.7) per 1000 m2 was recorded in the unplanned neighborhood compared to the planned neighborhood (3.4 trees and 2.0 species). A similar trend was noted in Kolwezi, although with significantly reduced values (by more than half). Across the two cities, a total of 36 fruit trees species were listed, of which 8 were exclusively identified in unplanned neighborhoods of Lubumbashi, showing a comparatively greater species richness of the city. Coincidentally, the 8 specific species are characteristic of Miombo woodland, suggesting preexistence of Miombo vegetation in these areas. Overall, the listed flora of studied neighborhoods in the two cities is dominated by exotic species, with Rutaceae the most represented family. Straightforward differences in the use of fruit trees were noted between the two cities; medicinal uses stand out in Lubumbashi, whereas uses such as shading and properties boundary predominate in Kolwezi. As common trend in the two cities, however, fruit trees scarcely receive arboricultural care, partly explained by limited knowledge on the ecological requirements of fruit trees. Current results have provided important insights into the botanical richness of fruit trees and related sociological aspects of their management at household-scale, which may help in formulating guidelines and technical tools to assessing and monitoring urban forestry in Southeastern DR Congo.

The Central African Copperbelt of the DR Congo and Zambia hosts more than 30 known Cu–Co hyperaccumulator plant species. These plants can accumulate extraordinarily high concentrations of Cu and Co in their living tissues without showing any signs of toxicity. Haumaniastrum robertii is the most extreme Co hyperaccumulator (able to accumulate up to 1 wt% Co), whereas Aeolanthus biformifolius is the most extreme Cu hyperaccumulator (with up to 1 wt% Cu). The phenomenon of Cu–Co hyperaccumulator plants was studied intensively in the 1970s through to the 1990s, but doubts arose regarding earlier observations due to surficial contamination of plant material with mineral particles. This study set out to determine whether such extraneous contamination could be observed on herbarium specimens of Haumaniastrum robertii and Aeolanthus biformifolius using scanning electron microscopy with energy-dispersive spectroscopy (SEM-EDS). Further, synchrotron X-ray absorption spectroscopy (XAS) was used to identify the chemical forms of Cu and Co in newly collected Haumaniastrum katangense plant material from the DR Congo. The results show that surficial contamination is not the cause for abnormal Cu–Co concentrations in the plant material, but rather that Cu–Co enrichment is endogenous. The chemical form of Cu and Co (complexation with carboxylic acids) provides additional evidence that genuine hyperaccumulation, and not soil mineral contamination, is responsible for extreme tissue concentrations of Cu and Co in Haumaniastrum katangense.

Phytostabilisation (i.e. using plants to immobilise contaminants) represents a well-known technology to hamper heavy metal spread across landscapes. Southeastern D.R. Congo, Microchloa altera, a tolerant grass from the copper hills, was recently identified as a candidate species to stabilise copper in the soil. More than 50 grasses compose this flora, which may be studied to implement phytostabilisation strategies. However, little is known about their phenology, tolerance, reproductive strategy or demography. The present study aims to characterize the Poaceae that may be used in phytostabilisation purposes based on the following criteria: their ecological distribution, seed production at two times, abundance, soil coverage and the germination percentage of their seeds. We selected seven perennial Poaceae that occur on the copper hills. Their ecological distributions (i.e. species response curves) have been modelled along copper or cobalt gradients with generalised additive models using logic link based on 172 presence-absence samples on three sites. For other variables, a total of 69 quadrats (1 m(2)) were randomly placed across three sites and habitats. For each species, we compared the number of inflorescence-bearing stems (IBS) by plot, the percentage of cover, the number of seeds by IBS and the estimated number of seeds by plot between sites and habitat. Three species (Andropogon schirensis, Eragrostis racemosa and Loudetia simplex) were very interesting for phytostabilisation programs. They produced a large quantity of seeds and had the highest percentage of cover. However, A. schirensis and L. simplex presented significant variations in the number of seeds and the percentage of cover according to site.

The differing properties of termite mound material compared to the surrounding soils are well-documented. Far less is known about their variability within the mounds themselves. Detailed sampling and physico-chemical analysis of four large Macrotermes mounds around Lubumbashi, D.R. Congo, revealed soil-related properties are far from uniform within the mounds. The total variability is highest perpendicular to the mound's surface. Based on mound morphology and variations in soil-related properties, four zones can be distinguished within the mounds: (i) the outer mantle, characterized by intense varied biological activity and by a well-developed soil structure; (ii) the active nest and chimney, found at the top, with the nest area as a site of organic matter mineralization; (iii) the accumulation zone, located in the lower central part of the mound, where compounds derived from the nest area are concentrated; and (iv) a transition zone, situated between the outer mantle and the other zones. Intermittent leaching plays a key role in the development of this zoning. The steep and smooth surface of the mound and the fine texture of the mound material limit the amount of percolating water in the rainy season. As a mound grows larger, this amount is no longer sufficient to leach mobile compounds to below ground level. At this stage of mound development, they accumulate in the lower central part of the structure. In view of their large size and high spatial density, a considerable part of the total nutrient stock of the ecosystem is likely contained within these large mounds.

This review synthesizes contemporary understanding of copper–cobalt (Cu–Co) tolerance and accumulation in plants. Accumulation of foliar Cu and Co to > 300 μg g−1 is exceptionally rare globally, and known principally from the Copperbelt of Central Africa. Cobalt accumulation is also observed in a limited number of nickel (Ni) hyperaccumulator plants occurring on ultramafic soils around the world. None of the putative Cu or Co hyperaccumulator plants appears to comply with the fundamental principle of hyperaccumulation, as foliar Cu–Co accumulation is strongly dose-dependent. Abnormally high plant tissue Cu concentrations occur only when plants are exposed to high soil Cu with a low root to shoot translocation factor. Most Cu-tolerant plants are Excluders sensu Baker and therefore setting nominal threshold values for Cu hyperaccumulation is not informative. Abnormal accumulation of Co occurs under similar circumstances in the Copperbelt of Central Africa as well as sporadically in Ni hyperaccumulator plants on ultramafic soils; however, Co-tolerant plants behave physiologically as Indicators sensu Baker. Practical application of Cu–Co accumulator plants in phytomining is limited due to their dose-dependent accumulation characteristics, although for Co field trials may be warranted on highly Co-contaminated mineral wastes because of its relatively high metal value.

Soil organic matter (SOM) dynamics and termite activity have now been widely accepted as key players for improving soil properties in tropical agro-ecosystems. Numerous studies have described environmental impacts of aboveground termite mounds, while few data are available on temporary structures built for food foraging, called termite sheetings. The effects of termite activity on soil properties resulting from organic matter (OM) amendment under two contrasting management practices were studied in similar pedological and climatic conditions in Southern India (Auroville). Our results showed an increase in bio-available nutrients (K, Mg and P), organic carbon (OC) content, cationic exchange capacity (CEC), exchangeable base cations and water pH in the termite sheetings compared to the underlying and reference soils, in the organic tilled field. On the other hand, only bio-available K increased in the permanent raised beds. Aggregation processes were improved in termite sheetings for the organic tilled field, as the amounts of macroaggregates (250 μm – 2 mm) and protected microaggregates increased, whereas the amount of free microaggregates (50–250 μm) decreased. Moreover, termite activity favoured SOM storage in termite sheetings by increasing OC content in each aggregate fraction, while no differences were observed in the permanent raised beds. Our study demonstrates that termite activity can improve nutrient availability, carbon storage and pH conditions in agro-ecosystems but that the magnitude of the effect likely depends on the agronomic practices in use.

Haumaniastrum katangense is well known as the “copper flower” of the Katangan Copper Belt. Few studies, however, are available on the physiology of this remarkable plant, including questions like stress responses and population-dependent differences. In the current study, we compared the response to copper for eight populations of this species in terms of copper accumulation, copper resistance, and various physiological parameters that might change under copper toxicity stress (biophysics of photosynthesis, growth, chlorophylls and carotenoids). Among six populations growing well under experimental conditions, three were found to be copper sensitive in terms of a strong inhibition of growth by 10 μM copper, while the other three were rather resistant. As the most prominent copper tolerance associated difference, copper resistant populations (as judged by their growth, photosynthetic activity and pigmentation) showed a decrease of iron accumulation in response to increased copper supply, while copper sensitive populations increased their Fe accumulation in response under these conditions. Copper sensitive populations showed the expected loss of pigments under copper toxicity stress, while two of the three copper tolerant populations even showed an enhancement of chlorophylls and violaxanthin in response to toxic copper. Also for other pigments population-specific differences in copper response were found, but they did not correlate with copper tolerance. Photosynthesis biophysics was affected by copper stress like in other species, no clearly tolerance/population-specific differences were found.

Background and aims - The occurrence of natural plant communities on Cuenriched substrates over significant areas of the earth's surface is exceptional. In Katanga (D.R.Congo), natural outcrops of copper-rich rocks are colonised by highly original plant communities. A number of plant species have been proposed as possibly endemic to those sites. Here we revise the taxonomic, phytogeographic and conservational status of these plants. Methods - Almost all the herbarium materials of supposed Cuendemics available in BR and BRLU have been revised and all relevant taxonomic revisions have been consulted. Literature and herbarium data have been supplemented by original observations in the field. Conservational status was established using IUCN criteria based on current and projected variation of population size and number. Key results - Thirty-two taxa are identified as strict endemics of Curich soil in Katanga, i.e. absolute metallophytes. Twenty-four of these are known from one to five localities only. Twenty-three other taxa are identified as broad endemics, i.e. with > 75% of occurrence on Curich soil. Fifty-seven other names formerly used for supposed endemics are rejected either for nomenclatural or phytogeographic reasons. A number of species formerly regarded as endemics have been discovered off copperenriched substrates due to progress in the botanical exploration of Katanga. The taxonomic value of a number of proposed endemics is still uncertain and requires further research. For a number of taxa, local geographic distribution still remains insufficiently known. The low proportion of endemics (c. 5%) in the flora of Curich soil in Katanga possibly indicates a recent origin of much of this flora. Arguments in favour of neoendemism and relictual endemism, respectively, are discussed briefly. Ten percent of strict endemics are extinct and 65% are critically endangered, due to actual or projected habitat destruction by copper mining. Endemics restricted to primary habitats may be the most difficult to conserve. Several species, mostly annuals, are able to thrive on secondary metalliferous habitats created by the mining industry and may thus be at lower risk. Conclusions - This review emphasizes the high conservation value of the flora of Curich soil in Katanga and should help prioritise future conservation efforts. © 2010 National Botanic Garden of Belgium and Royal Botanical Society of Belgium.

Essential oils of aromatic plants are nowadays cited as suitable tools for better protection of stored grains from insect pest attacks. These chemical insecticides are less attractive to producers because of their low persistence and difficulty to use as pure product There is therefore a need to formulate them as an easy handling chemical with better persistence. The present work aimed to study the formulation through adsorption of active components of Xylopia aethiopica Dunal (Annonaceae) essential oil on kaolin. X aethiopica essential oil was obtained by hydrodistillation in a Clevenger type apparatus unit Essential oil obtained was analysed by a GC-FID and a GC-MS. The adsorption measurements were performed with collected two kaolin fractions (F1

Hyptis spicigera essential oils from seven localities in the North-Cameroon (Ngaoundere, Guirvidig, Kodeck, Lara, Toloum, Kaele, Tchecal-baila) were investigated by GC and GC/MS. Results showed differences within harvesting sites and between the different sites of collection but did not revealed clear tendencies in the evolution of the oil composition with regard to the sampling period. The main group of compounds in all the analyzed samples were: alpha-pinene (11.9%-42.1%), beta-pinene + sabinene (6.0%-39.8%) and beta-phellandrene + 1,8-cineole(8.8%-27.4%) except in one oil where beta-caryophyllene (23.4%) was the principal component. The insecticidal activity of H. spicigera and its principal terpenic components was evaluated against the cowpea weevil Callosobruchus maculatus F., the major cause of damages of cowpea (Vigna unguiculata (L.) Walp) in North Cameroon.

The acute toxicity of essential oils from the whole fruit (EF) or from the fibres of the fruit (FF) of the local aromatic plants Xylopia aethiopica Dunal (Annonaceae) collected in north Cameroon was evaluated on Sitophilus zeamais adults. A concentration of 1 ml of essential oil per 100 g of maize seeds was tested to determine weevil mortality after 24 h of exposure. Under these conditions, the essential oil derived from both EF and FF of X. aethiopica led to 100% mortality. In a second step, proportions of active compounds present in the oil of both EF and FF of X. aethiopica were quantified. The toxicity of the four main compounds was tested against S. zeamais: alpha-pinene, beta-pinene, Delta-3-carene and terpinen-4-ol according to their proportion in the essential oil of the concerned plant part. beta-pinene and terpinen-4-ol were responsible for 50% of the mortality at the proportion found in EF and FF essential oils respectively. When mixed, a synergic effect of the compounds was observed that restored the mortality percentage observed for the crude oil. It appears that X. aethiopica essential oil could be a potential source of natural and low-cost insecticide to control storage pests.

Mycotoxins are naturally occurring toxic chemical compounds produced by fungi infesting agricultural crops both during crop growth and storage. Such secondary metabolites, when ingested, can produce toxic syndromes in humans. This study is the first survey that documents the occurrence of mycotoxins in stored barley in Tibet Autonomous Region [P.R. China]. Twenty-five samples of barley collected from Tibet were analyzed for the presence of aflatoxins, fumonisins, ochratoxins, zearalenone, deoxynivalenol, and T-2 toxin using an easy, sensitive, competitive direct enzyme-linked immunosorbent assay. Ninety-six percent of the samples were contaminated with zearalenone at concentrations ranging from 25 to 270 µg/kg. Seventy-six percent of the samples were contaminated with T-2 toxin at concentrations ranging from 1 to 163 µg/kg. In contrast, deoxynivalenol was observed in only 12% of the samples, with toxin concentrations ranging from 25 to 270 µg/kg. Aflatoxin was observed in only 4% of the contamina...

Composition des huiles essentielles de Xylopia aethiopica (Dunal) A. Rich du Cameroun et identification d’un diterpene : ent-13-epi manoyl oxyde. L’huile essentielle des infrutescences de Xylopia aethiopica (Annonacee), de quatre localites du Cameroun, a ete analysee par GC/MS et GC/FID. Plus de soixante composes ont ete identifies avec 47,5–84,0 % de monoterpenes hydrocarbones, principalement le b-pinene et un melange de b-phellandrene et de 1,8-cineole, 6,5–12,9 % de monoterpenes oxygenes, 13,8–30,4 % de sesquiterpenes, et 0,4–0,6 % d’un diterpene non identifie. Les essais de purification sur colonne chromatographique et des analyses par GC/MS et RMN ont permis d’identifier ce diterpene comme etant le ent-13-epi manoyl oxyde qui est rapporte pour la premiere fois dans l’huile essentielle des fruits de X. aethiopica.

Kashin-Beck disease occurs in several villages of Tibet; however, its local importance varies greatly. The ecoclimatological as well as the phytogeographical framework of the studied area are presented. An ecological approach based upon the ethno-ecosystem concept was carried out in the vicinity of each village. This study identifies 18 vegetation units on a structural basis; they were named for the dominant plants of each unit. Half of them belonged to the aquatic milieu. The different factors controlling their distribution were also identified. Particular attention will be paid to the links between man and the environment, particularly regarding alternative food intakes and water supply access.

The impact of dolomite lime (5 t ha −1 ) on the moss layer was investigated in a Belgian Norway spruce ( Picea abies (L.) Karst.) forest. Bryophytes reacted rapidly, showing a decrease in frequency, cover and biomass of acidophilous dominant Dicranaceae species. Some neutrophilous competitive or stress tolerant species were spreading out and some ruderals appeared. The reaction of the dominant species coverage to different liming rates was also considered. Results showed that the negative effect was more pronounced than higher dolomite doses were.

This paper is part of an ecological study designed to outline a conservation plan for a natural wetland area located in the Loire alluvial plain of Burgundy (Sologne bourbonnaise). In this part of the river (upstream from Decize), the meandering characteristics of the channel system are very different from those that occur downstream from its confluence with the Allier river. After a brief synopsisof the geographical characteristics of the Loire valley in Burgundy, the changing dynamics of the Loire along a 40 kilometre stretch of river are studied through an analysis of channel shifts and meander evolution between 1967 and 1992. The intensity and occurrence of floods recorded at Never s from 1852 to 1985 are presented. They provide a good idea of channel evolution in natural conditions prior to the construction of the Villerest dam. A perceptible decrease in the average wavelength (13 m), and an increase of the curve index can be distinguished, but generally, variations in meander morphometry have been very small during the 25 years of interest. The relative meander stability was compared with river activity as inferred from temporal changes in sand bank surfaces. The results show that the active channel surface decreased by 13 % between 1967 and 1992. This is far from insignificant and is clearly indicative of a change in stream energy. This analysis is supplemented by the more detailed morphodynamic study of a small area ( "Г île de la Crevée ") spanning a period of more than 230 years. From 1760 to 1852, lateral shifting of the river bed, in relation to major flooding, was considerable. Both of these spatio-temporal studies testify to a recent stabilisation of channel systems in the Loire. The situation since 1967 is largely stable. This is ascribable to a decline in major flooding events and is reflected in the near stability of meanders, with a, Résumé Après un bref rappel des caractéristiques géographiques ligériennes dans le secteur concerné, une étude d'un tronçon de 40 kilomètres de lit fluvial a permis de mettre notamment en évidence les divagations du fleuve dans le lit mineur, l'évolution du méandrage en 25 ans (1967-92) et d'apprécier l'activité de la Loire. Par ailleurs, une seconde approche morphodynamique, s'étalant sur une période de plus de 230 ans, a été réalisée sur un secteur de dimension réduite : l'île de la Crevée. Ces études spatio-temporelles mettent en exergue, l'une et l'autre, un ralentissement récent de l'activité de la Loire dû à l'absence de grandes crues et se traduisant par une quasi-stabilité des méandres, avec pour conséquence une fermeture du lit par l'extension de la ripisylve., Leteinturier Béatrice, Engels Patrick, Petit François, Chiffaut Alain, Malaisse François. Morphodynamisme d'un tronçon de Loire bourbonnaise depuis le XVIIIe siècle / Changing dynamics of the Loire river in Burgundy (France) during the last 200 years. In: Géomorphologie : relief, processus, environnement, Octobre-décembre, vol. 6, n°4. pp. 239-251.

Tylosema fassoglensis seeds contain high levels of lipids (240-300 g kg -1 ) and proteins (446 g kg -1 dry weight). Major fatty acids contained in the oil are linoleic (36-42% of the total fatty acids) oleic (32-35%) and palmitic (11.5-15.7%) acids. The proteins are characteristic with their high levels of lysine, proline and tyrosine. Due to their very low content, both methionine and cystine appear to be the limiting amino acids. Tylosema fassoglensis defatted meal contains substantial amounts of trypsin inhibitors and phytates 295 TUI mg -1 and 35 g kg -1 dry weight, respectively

Plant communities of soils naturally enriched in copper and cobalt in Katanga (D. R. Congo) are critically threatened in the short term due to mining activities. For biodiversity conservation and ecosystem restoration purposes, there is an urgent need to acquire more knowledge on those plant communities including their diversity and their relationships to environmental factors. The classification of 62 vegetation plots located in 6 metal-rich rocky hills in the Tenke Fungurume mining area resulted in 3 well-defined steppic and steppic savanna communities. Canonical analysis showed that the community comprising the largest proportion of strictly endemic metallophytes (i.e. species that only occur on metal-rich soils) developed in the soils with the most elevated concentrations of Cu and Co. However, contrasting species assemblages in the two other plant communities were explained by soil nutrients and percentage rocks in addition to heavy metal concentrations. The results of this study will assist with restoration efforts because they (1) provide a rigorous assessment of communities before a disturbance and (2) define essential edaphic conditions needed for the reestablishment of critical communities., FLWIN, info:eu-repo/semantics/published

Plants that have evolved to survive on metal-rich soils-metallophytes-have key values that must drive research of their unique properties and ultimately their conservation. The ability of metallophytes to tolerate extreme metal concentrations commends them for revegetation of mines and metal-contaminated sites. Metallophytes can also be exploited in environmental technologies, for example, phytostabilization, phytoremediation, and phytomining. Actions towards conserving metallophyte species are imperative, as metallophytes are increasingly under threat of extinction from mining activity. Although many hundreds of papers describe both the biology and applications of metallophytes, few have investigated the urgent need to conserve these unique species. This paper identifies the current state of metallophyte research, and advocates future research needs for the conservation of metallophyte biodiversity and the sustainable uses of metallophyte species in restoration, rehabilitation, contaminated site remediation, and other nascent phytotechnologies. Six fundamental questions are addressed: (1) Is enough known about the global status of metallophytes to ensure their conservation? (2) Are metallophytes threatened by the activities of the minerals industry, and can their potential for the restoration or rehabilitation of mined and disturbed land be realized? (3) What problems exist in gaining prior informed consent to access metallophyte genetic resources and how can the benefits arising from their uses be equitably shared? (4) What potential do metallophytes offer as a resource base for phytotechnologies? (5) Can genetic modification be used to "design" metallophytes to use in the remediation of contaminated land? (6) Does the prospect of using metallophytes in site remediation and restoration raise ethical issues? © 2004 Society for Ecological Restoration International.

The Louisiana red swamp crayfish, Procambarus clarkii, has had a major impact on aquatic ecosystems in Europe and America where it has been introduced for human consumption. In Lake Naivasha, where it was introduced in 1970, it is suspected of causing the complete disappearance of native floating-leaved and submerged plants by 1982 and again by 1996; recovery of submerged plants occurred in between, concurrent with a decline in P. clarkii. Examination of the feeding of P. clarkii by microscopic analysis of gut contents collected from the lake confirmed information from both its native and exotic ranges; that it is an omnivore with green plants and insects the predominant items recognised. Feeding experiments confirmed this omnivory, with a preference from herbivory over carnivory. They further showed the importance of native plants as opposed to exotic water hyacinth Eichhornia crassipes. It is concluded that P. clarkii could well have accounted for the observed elimination of native plant species in Lake Naivasha; the cyclical nature of populations of submerged plant species and of P. clarkii in inverse proportion to each other lead us to hypothesise that P. clarkii is a ‘keystone’ species in the lake ecosystem.

Starting from the information gathered in the revision of the Orchidaceae for the Flore d’Afrique centrale (Geerinck 1984, Geerinck et al. 1992) as well as from the recent paper dealing with the Orchids of Burundi (Arbonnier & Geerinck 1994), the present contribution firstly discusses diversity both at specific and infraspecific levels for the Upper Katanga district of Zaire. Amongst the 587 taxa of the Flore d’Afrique centrale, some 313 were recognized as present in Upper Katanga (53%), of which 121 present a distribution restricted to the Zambezian phytogeographical regional centre of endemism. Six main patterns of distribution are recognized, some with very restricted area. Two examples of speciation are analyzed, namely for the genus Kryptostoma (Summerh.) Geerinck and for the section Multipartitae Kraenzlin of the genus Habenaria Willd.

Essential oils of aromatic plants with insecticidal properties are nowadays considered as alternative insecticides to protect stored products from attack by insect pests. A combination of some of these plants in the granaries is a current practice in certain localities of northern Cameroon. The aim of the present work was to analyze the impact of the combinations of the essential oils of Vepris heterophylla (Rutaceae), Ocimum canum, and Hyptis spicigera (both Lamiaceae), the three most used local aromatic plants because of their insecticidal activity and their repellent effect on Sitophilus oryzae. The present work revealed that these plants are rich in monoterpenoids. The GC/MS analyses have shown that monoterpenoids represented 65.5% for H. spicigera, 92.1% for O. canum and 47.0% for V. heterophylla. The crude essential oil of O. canum was the most insecticidal with a LD50 of 42.9 ppm. The most repellent effect was obtained by a combination of the essential oils of H. spicigera and O. canum, with a repellent percentage at 77.5%. These results suggest a suitable strategy for pest management of stored products.